Sunflower growers have another weapon available to them this year in their dealings with sunflower moth and/or banded sunflower moth.

That weapon is Prevathon®, an insecticide product of DuPont. Prevathon, which received federal registration in 2011, was approved by EPA for use on sunflower in late October of 2012. The main sunflower-producing states in the Northern Plains as well as the Southern Plains are among the numerous states in which this insecticide is registered.

FIFRA 2(ee) labels indicate that Prevathon is effective on many insects in the Order Lepidoptera (moths), as well as on Colorado potato beetle and grasshopper nymphs. It is “powered” by DuPont’s Rynaxypyr® chemistry, which is a different mode of action from the pyrethroid and organophosphate groups. “Rynaxypyr produces muscle paralysis, rapid feeding cessation and death among leaf-feeding insects in either the larval (caterpillar) or adult stage,” explains Janet Knodel, extension entomologist with North Dakota State University. “It also works as an ovi-larvicidal insecticide on the moths; so as the young larvae hatch from the eggs that have been sprayed with Prevathon, they die as soon as they’re exposed to the chemical.”

Knodel affirms that the new mode of action that Prevathon brings to the table should help open doors for its use against the sunflower moth and banded sunflower moth. Data from 2011 and 2012 NDSU and Kansas State University insecticide evaluation trials “have shown it’s very efficacious against those two insects,” Knodel reports.

Economic thresholds and timing for use of Prevathon for control of the sunflower moth and banded sunflower moth are similar to those already in place, Knodel notes. So treatment for seed-infesting insects would be recommended when populations of those insect pests are at the economic threshold level and sunflower plant growth is at the R5.1 stage (10% of disk flowers open).

Another apparent benefit of Prevathon is a residual activity period that’s significantly longer than that of the pyrethroid and organophosphate insecticides. Based on DuPont research data, Prevathon provided about a 30-day-long residual. Knodel still plans to test this parameter as well.

Prevathon is very stable at high temperatures, and toxicity data show that it is quite safe. Bee toxicity studies using Coragen®, a “sister insecticide” to Prevathon, have demonstrated low (but not zero) toxicity to bees. DuPont believes that the bee toxicity profile for Prevathon would be quite similar. The company recommends against direct sprays of bees or other beneficial insect pests, however

“Prevathon is very compatible for tank mixing with other insecticides, fungicides and fertilizers, notes NDSU’s Knodel. “However, it’s always a good idea to do a jar test (to check for separation) before mixing it in your commercial tank.” The field re-entry period after treatment is just four hours.